A controversial appeals court nominee from Nebraska, who received a rare unanimous “not qualified” rating from the American Bar Association, has revived concerns about whether the legal organization is biased.

The organization has long conducted nonpartisan reviews of federal judicial nominees and rated them for the Senate Judiciary Committee. The vast majority of the time the group finds a nominee “qualified” or “well-qualified,” and has done so even with the numerous controversial judge picks President Donald Trump has made.

But now the ABA has agreed to appear before the committee Nov. 15 to answer questions about its rating for Steve Grasz, a nominee for the U.S. Court of Appeals for the 8th Circuit, as well as its rating process generally. Grasz is the first appeals court nominee to get such a rating since 2006, and that pick was then withdrawn.

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The evaluators conducted more than 200 confidential interviews and spoke twice with Grasz, an Omaha lawyer and lobbyist. Grasz once defended the state’s “partial birth abortion” ban at the Supreme Court as the state’s deputy attorney general and previously served on the board of the Nebraska Family Alliance, a faith-based organization that has staked out controversial positions on LGBT rights.

“The evaluators found that the people interviewed believed that the nominee’s bias and the lens through which he viewed his role as a judge colored his ability to judge fairly,” the ABA report states. “It was also clear that there was a certain amount of caginess, and, at times, a lack of disclosure with respect to some of the issues which the evaluators unearthed.”

“When I look at Mr. Grasz’s resume, it appears that he’s eminently qualified to be a circuit court judge,” Judiciary Chairman Charles E. Grassley of Iowa said of why he invited the ABA to testify this month.

Sen. Deb Fischer, who introduced Grasz at the hearing, called the ABA rating “a baseless political character assassination” that was filled with innuendo and led by two evaluators who have won awards from or donated to Democrats.

“For these two individuals to suggest that Steve’s participation in the democratic process or his passionate advocacy while serving as deputy attorney general for the state of Nebraska are somehow disqualifying for serving on the bench? It seems to me to be the height of hypocrisy,” the Nebraska Republican said.

Yet the ABA listed reasons for its 14-0 vote in its recommendation, Rhode Island Democratic Sen. Sheldon Whitehouse pointed out at the Grasz hearing. The reasons cited include being biased, “gratuitously rude” and having a history of pursuing a social agenda and partisan politics.

The report also cited an atmosphere of unusual fear that there could be potential repercussions for speaking against Grasz, who is politically well-connected. Forty of Trump’s 42 judicial nominees have received good recommendations from the ABA, Whitehouse noted.

“I think it would be hard for the committee to ascribe the outcome in this case to a general partisanship of the ABA,” Whitehouse said. “It wouldn’t be consistent with the facts.”

It was easy for Sen. Jeff Flake, who said he has long had concerns about the ABA’s rating process. “I think the ABA’s long history of liberal political activism makes it hard to see how their process isn’t biased,” the Arizona Republican said.

Sen. John Kennedy said he believed the evaluators didn’t like that Grasz was against abortion rights. “They just don’t like your politics,” the Louisiana Republican told Grasz.

Democrats used the confirmation hearing Wednesday to press Grasz on his past views on abortion and LGBT rights, such as a 1996 opinion he wrote that concluded same-sex marriage rights would be a “grave danger” to Nebraska’s marriage laws.

Liberal advocacy groups such as Lambda Legal have criticized Grasz for family connections to the Nebraska Family Alliance, where his son is policy director, and its positions on gay-conversion therapy and other LGBT issues.

“The topic of conversion therapy has never been part of my legal practice or been part of my life,” Grasz told senators Wednesday.

The committee won’t vote on Grasz’s nomination until after the Nov. 15 hearing with the ABA testimony, Grassley said.